This is why Redline D6 is not the best ATF in Prius

I am using high performance fluid and use a high performance OCI. I require excellent wear numbers and will pay for that. I'm funny like that. I do not intend to leave the fluid in the gearbox longer than 25,000 miles so TAN mitigation is not a concern to me. In all the cars I have owned since I started wrenching on cars as a kid I have never let the trans fluid go longer than 30,000 miles. The result is I have never seen the waiting room of an Aamco.
Ever. It's very cheap to avoid that.

I calculated that TAN number of D6 on my first UOA. How long in the Prius gearbox before it starts getting acidic.
TAN mitigation is dealt with by the additive pack found in WS primarily Calcium. Calcium is also a wear component. Side by side my pure poly ester base stock fluid will outperform WS in base wear. No contest. Its silly to disagree with that. But TAN is a concern. Would I leave it in the box and forget it no way. I also require high performance oil in my engine and pay for that luxury. Everyone understands that but when you start discussing different fluids in the trans a lynch mob quickly assembles. I attribute this to mostly Prius Chat your windings are going to melt hysteria.

6 years later my trans runs perfect. What more do you require?

So.......WS in the box never change it ever great it will probably last a very long time if you don't drive the car like a hot rod. But, super duty the car and you'll pay alot more than I ever will.

 

I've associated total acid number (TAN) as a by-product of micro-dieseling. Given the other by-products, I've never considered TAN to be that big of a problem. Still, do you have any metrics on transaxle service and TAN changes?

We are on the same sheet of paper about this. What drives me nuts is the term 'synthetic' apparently means some blending of dino oil is allowed.

I think there are materials issues that have yet to be throughly investigated. In particular, molybdenum disulfide remains a question as I can find no evidence of its use in the Toyota ATF fluids. Yet this strikes me as being an ideal candidate for a dry lubricant, additive to our Prius transmissions . . . especially those with silent chains like the NHW11/NHW20.

I would also like to know more about the anti-foaming additives. It isn't clear that they would provide a significant reduction in micro-dieseling in our particular transaxles.

Bob Wilson

 

Bob I can only compare the Prius to other manual boxes I have owned that used trans fluid and the Prius seems to turn its trans fluid acidic quicker than I have previously seen. I have no other metrics other than that. So to be on the safe side I base lined life/tan level so I know when to dump it. Even if I ran WS I would use the same OCI so why not use the best GL-4 I can get my hands on. Its the same price.

Whats kills this trans is high current demand from the mg overheating the windings which makes the winding insulation/coating fail and the resultant blow out. Classic electric motor failure. If you like to pummel this little car up hills alot with big weight loads you better have fresh trans fluid and fresh I coolant on board.

When Redline states synthetic its pure base stock no blending. And I have never seen MolyB in atf. That's usually found in motor oil additives that promise the world.

I'm coming up on my second atf change at 59,000 miles and this one will be 25,000 miles on D6. I will post the UOA. I expect to see excellent wear numbers.

 

In this we agree:

Or a lot of +75 mph driving, MG2 can easily exceed 100C and that is bad news. I'm sure that is what was cooking the transaxle oil in our 2003 Prius before I bought it. It is also why I am after lower viscosity as I know this reduces the mechanical heating, the stirring losses.

The good thing is we have folks using oil testing to figure out what is actually happening in the transmissions. It sure beats the all too common FUD posted about what is going on.

After folks get the initial debris out of the transaxle, they work pretty darn good. I keep thinking about micro-filtration options but I hate the current 'plumbers nightmare.' Doug actually had one put in an NHW11 but I understood it was taken out later.

Bob Wilson

 

Bob, are you saying someone tapped into the oil pump passages and installed some sort of bypass oil filter on a Prius transaxle? I know Gen1, 2, 3. I don't know the numbers you are using.
I'd like to see this installation!

Although, just adding a magnet to the drain plug adds some 'filtering'. I should have taken a picture of mine.
My method works, but for the nervous there is this site: Automotive Magnetic Oil Drain Plugs AP-05

 

Almost 2 years later! Hope you're doing well. Any updates on your studies of transaxle fluids?

 

I bought my 07 new and 5,000 miles later moved over to Redline D6. Fluid looked pretty black. It was surprising. Now at 80, 000 miles and changed it for the third time at 75,000 miles with at that time had 35,000 miles on that fluid interval. Last change it saw. The fluid looked almost new bright red etc so I didn't bother with a UOA.

Majority of the trans wear in a Prius happens the first 15,000 miles. All the differential gears are breaking in. The diff's sustain the most load and impact in the trans.

My new interval will be every 50,000 miles now. I have invested so far in trans fluid changes in the last 7 years about $150.

The G3 Prius trans fluid the few pics I have seen look really bad at initial miles.

 

That was my experience too, after the fluid has been changed before, it seems to stay nice, red and clean. What is the price difference of WS vs D6?

 

Redline D6 is $11.95 a quart. Jegs used to offer free ship but I was told yesterday they stropped that.

 

ooops...price increase $12.49 a quart.

 

Hello Bob, I see temps of 100C+ in the city on my SG? If it so bad why does it go that high in the first place?

If I use D6 does that make it ok then if I hit temps of 250F+?

 

excellent thread & discussion guys. Been using D6 in my Rav4 for a while, no issues. First I'm hearing re: no calcium additive for preventing acidity, but great to hear D6 is running well for you guys. Have you considered Amsoil's ATL? Operating viscosities are in line, and looks like calcium is 275ppm (google amsoil atl voa). This may be an appropriate alternative over D6?

 

Been using redline trans oil for over 30 years. Tan is no big deal in a manual trans but to be on the safe side in g2 box that has motor windings I pulled some uoa's just to see how the tan looked and it was as expected especially how hard I drive the car. It spends its life at 75 mphs.
But given how tough and well built the g2 trans is I could probably run it for 200000 miles no problem. But it's so easy to change the fluid on this car it's no big deal. 110,000 miles later on D6 it is superb.

In a rav I would not give it a thought. I would change it at say 75000 miles and see how it's doing though. You have the best trans fluid on the market in your car.

 

If you want to try something really cool try Redline motor oil. 5-30.
It makes your engine sound different and much much smoother.
If you buy some compare it to regular oil Between your fingers.
It's some crazy slippery stuff. It's like liquid plastic. Pure synthetic oil not hydro cracked oil.
It really quiets down the very noisey solid lifter g2 motor.

 

run redline 5w30 in my mini and my evo. i've been running amsoil in the corolla & rav4 for extended drain intervals with better success, redline imo does better protecting against hard usage.

 

I am impressed with how much the redline oil quiets down our clakity clack solid lifter g2 motor. It's got an excellent zddp package. I run it in my P71 Crown Vic to and that 4.6 loves it. Big difference from Mobil 1.

 

I'm at 106,000 miles on my bought new 07 running Redline D6. Trans run perfect.
I changed the trans fluid with D6 at:

5000 miles fluid very dark UOA
35,000 miles fluid slightly dark UOA
75,000 miles fluid looks almost new

Now at 106K.

I am able to change it so frequently (once every 3 years) because its so easy to change. If it was a hassle probably not.
Based on what I am seeing I will probably never change it again....maybe at 200K. I have invested $200 in trans maintenance over the last 10 years including 2 UOA's.

Have not changed it since the 75K change as its clearly a break in issue. From what I have seen on my bought new car is replace the trans fluid at 5,000 miles and it will probably never need another change on a G2. Alot of initial differential gear and chain break in I suspect.
The same probably goes for the G3 except no chain in G3. Initial photos of G3 fluid look bad. Milkshake like a diff change.

 

Drained fluid appearance will be like that with Toyota ATF-WS too.

 

Because Toyota adamantly states in the Owner's Manual to use nothing but Genuine Toyota ATF WS, or risk damage? Ah, what's the use, lol.

Seriously, you should use "at your risk" disclaimers, when you proselytize alternative transaxle fluids.